title: Dose-dependent toxicity of ethylene glycol monomethyl ether vapour in the rat.
abstract: Wistar male rats were exposed by inhalation to 50, 100 or 400 ppm of ethylene glycol monomethyl ether (EGME) for 1 to 2 weeks. The overall hepatic drug oxidation reactions, O-deethylation of 7-ethoxycoumarin and 7-ethoxyresorufin and cytochrome P-450 content were only slightly affected by the EGME exposures. NADPH cytochrome c reductase activity showed a tendency toward a dose-dependent decrease in liver, the activity being 73% and 64% of that in the controls after one and two weeks of exposure, at 400 ppm respectively. UDP glucuronosyl transferase activity exhibited a dose-dependent enhancement in liver microsomes after exposure for two weeks to EGME. The enhancement was 1.3- 1.7- and 3.0 fold with exposure to 50, 100 and 400 ppm of EGME respectively. After exposure for one week the UDPglucuronosyltransferase activity in kidney microsomes was similarly enhanced. A dose-related increase in measurable UDPglucuronosyltransferase activity was also obtained in Triton X-100 treated hepatic microsomes. GSH levels of the liver and kidneys in EGME treated animals showed a tendency towards a dose-dependent increase. The activities of low-Km and high-Km aldehyde dehydrogenases in liver were decreased 6 - 14% of that in the controls with exposure to 400 ppm of EGME when glycolaldehyde was used as a substrate. Serum alanine aminotransferase activity was not influenced by inhalation exposures to EGME.
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005026:Ethylene Glycols / Q000378:metabolism / Q000633:toxicity*; D014453:Glucuronosyltransferase / Q000032:analysis; D005978:Glutathione / Q000032:analysis; D007668:Kidney / Q000187:drug effects* / Q000201:enzymology; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D009251:NADPH-Ferrihemoprotein Reductase / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D014835:Volatilization
chemical_list: D005026:Ethylene Glycols; D009251:NADPH-Ferrihemoprotein Reductase; D014453:Glucuronosyltransferase; C005219:methyl cellosolve; D005978:Glutathione